Processing system having a front opening unified pod (foup) load lock

ABSTRACT

An embodiment is a processing system for processing a substrate. The processing system includes a Front Opening Unified Pod (FOUP) load lock (FLL) and a vacuum system. The FLL has walls defining an interior space therein. The FLL includes load lock isolation and tunnel isolation doors. The load lock isolation door is operable to close a first opening in a first sidewall of the FLL. The first opening is sized so that a FOUP is capable of passing therethrough. The tunnel isolation door is operable to close a second opening in a second sidewall of the FLL. The second opening is sized so that a substrate is capable of passing therethrough. The vacuum system is fluidly connected to the interior space of the FLL and is operable to pump down a pressure of the interior space of the FLL.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. ProvisionalPatent Application No. 62/733,563, entitled “Processing System having aFront Opening Unified Pod (FOUP) Load Lock,” filed on Sep. 19, 2018,which is incorporated herein by reference in its entirety.

BACKGROUND Field

The present disclosure generally relates to a processing system forprocessing a semiconductor substrate, and more particularly, to aprocessing system having a Front Opening Unified Pod (FOUP) load lock.

Description of the Related Art

Forming an integrated circuit on a semiconductor substrate (e.g., wafer)generally includes numerous different processes. Each of these processescan be performed by a processing system (e.g., a tool) that has one ormore processing chambers. These various processing systems are usuallyhoused in a fabrication plant or facility (e.g., a “fab”). Thesubstrates can be transported between different processing systems usinga Front Opening Unified Pod (FOUP).

Cleanliness of the processing systems in the fab and of the substratesprocessed by the processing systems may affect performance of theresulting integrated circuit. A particle of dust or other debris in aprocessing system can prevent proper processing of the substrates. Fabsare generally designed to ensure a proper level of cleanliness (e.g.,Class 1 cleanroom standard, etc.). However, particles may still beintroduced to the fab. Hence, an opening at an interface between aprocessing system and the ambient environment of the fab can introduceparticles into the processing system.

SUMMARY OF THE DISCLOSURE

An embodiment is a processing system for processing a substrate. Theprocessing system includes a Front Opening Unified Pod (FOUP) load lockand a vacuum system. The FOUP load lock has walls defining an interiorspace therein. The FOUP load lock includes a load lock isolation doorand a tunnel isolation door. The load lock isolation door is operable toclose a load lock isolation door opening in a first sidewall of the FOUPload lock. The load lock isolation door opening is sized so that a FOUPis capable of passing therethrough to and from the interior space. Thetunnel isolation door is operable to close a first slit valve opening ina second sidewall of the FOUP load lock. The first slit valve opening issized so that a substrate capable of being placed in the FOUP is capableof passing through the first slit valve opening to and from the interiorspace. The vacuum system is fluidly connected to the interior space ofthe FOUP load lock. The vacuum system is operable to pump down apressure of the interior space of the FOUP load lock.

Another embodiment is a method for providing a substrate to a processingsystem. A first Front Opening Unified Pod (FOUP) is positioned at a loadlock door opening of a FOUP load lock. Using a shuttle, the first FOUPis transferred through the load lock door opening to an interior spaceof the FOUP load lock. After transferring the first FOUP to the interiorspace, a pressure of the interior space is pumped down. Using theshuttle, the first FOUP is positioned at a slit valve opening of theFOUP load lock.

A yet further embodiment is a processing system for processing asubstrate. The processing system includes a Front Opening Unified Pod(FOUP) load lock, a vacuum system, a transfer chamber, and a processingchamber. The FOUP load lock is configured to receive a FOUP in aninterior space of the FOUP load lock. The vacuum system is fluidlyconnected to the interior space of the FOUP load lock. The vacuum systemis operable to pump down a pressure of the interior space of the FOUPload lock. The transfer chamber is attached to the FOUP load lock. Thetransfer chamber comprises a transfer robot. The transfer robot isoperable to transfer a substrate from the FOUP in the interior space tothe transfer chamber. The processing chamber is attached to the transferchamber. The transfer robot is operable to transfer a substrate from thetransfer chamber to the processing chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate only someexample embodiments of this disclosure and are therefore not to beconsidered limiting of its scope, for the disclosure may admit to otherequally effective embodiments.

FIG. 1 is a simplified schematic top view of an illustrative processingsystem, according to some examples.

FIG. 2 is a cut-away perspective view of the processing system of FIG.1, according to some examples.

FIGS. 3 through 8 are partial cut-away perspective views of theprocessing system of FIG. 1 illustrating a sequence of operations forloading a Front Opening Unified Pod (FOUP) to a FOUP load lock,according to some examples.

FIGS. 9 through 11 are partial cut-away perspective views of theprocessing system of FIG. 1 illustrating a sequence of operations fortransferring a FOUP into and/or out of an interior space of the FOUPload lock and for transferring substrates between the FOUP and atransfer chamber, according to some examples.

FIG. 12 is a simplified schematic top view of another illustrativeprocessing system, according to some examples.

To facilitate understanding, identical reference numerals have beenused, wherever possible, to designate identical elements that are commonto the figures. It is contemplated that aspects of one embodiment may beused in other embodiments, without further recitation.

DETAILED DESCRIPTION

Examples described herein related to a Front Opening Unified Pod (FOUP)load lock that can be incorporated into a processing system. The FOUPload lock includes a shuttle that can transfer a FOUP into and out of aninterior space of the FOUP load lock. The FOUP load lock can have FOUPdoor opening capabilities and can have substrate mapping capabilities.The shuttle can index the FOUP so that a transfer robot can directlyaccess semiconductor substrates (e.g., wafers) in the FOUP. The FOUPload lock can include a FOUP transfer and queueing elevator system,which can function as an interface between the FOUP load lock and anoverhead hoist transfer (OHT) system. If implemented, the FOUP transferand queueing elevator system can stage an additional FOUP whilesubstrates from another FOUP in the FOUP load lock are being processedby the processing system. This staging can reduce down time of theprocessing system. Among other possible benefits, the FOUP load lock caneliminate or obviate some components of previous systems, and can reducea footprint and cost of the processing system.

Various aspects of different examples are described below. Althoughmultiples aspects of different examples may be described together in aprocess flow, the multiple aspects can each be implemented separately orindividually and/or in a different process flow. Additionally, variousprocess flows are described as being performed in an order; otherexamples can implement process flows in different orders and/or withmore or fewer operations.

A FOUP, as implemented in the examples described below, can havedifferent constructions. For example, a FOUP can have or be a plasticenclosure. A FOUP with a plastic enclosure may be vented so that apressure inside the FOUP is the same as the pressure of the ambientenvironment of the FOUP. In other examples, a FOUP can have or be anenclosure formed of a metal or other rigid material with sufficientstrength to maintain the structural integrity of the FOUP when a vacuumis applied within the FOUP and the ambient environment is, e.g., oneatmosphere (atm). In examples where the FOUP implements an enclosureformed of a metal or other rigid material, the FOUP may be maintainedoutside of a processing system (e.g., during transport betweenprocessing systems) in a vacuum or reduced pressure state, which canreduce the likelihood of an incidence of dust or other particles in theFOUP. In further examples, a FOUP can have or be an enclosure formed ofa metal or other rigid material, which is vented. A FOUP can have one ormore slots (e.g., 25 slots) each for placing a semiconductor substrate(e.g., wafer), such as for storage and transport. The FOUP canaccommodate any size of substrate, such as a 200 mm diameter substrate,300 mm diameter substrate, or a 450 mm diameter substrate.

FIG. 1 is a simplified schematic top view of an illustrative processingsystem 100, according to some examples. The processing system 100includes a FOUP load lock 104, a transfer chamber 106, a transfer (e.g.,tool and material handling) robot 108 within the transfer chamber 106, afirst processing chamber 110, a second processing chamber 112, a thirdprocessing chamber 114, a fourth processing chamber 116, and a fifthprocessing chamber 118. The processing chambers 110, 112, 114, 116, 118each may be any appropriate processing chamber, such as for a depositionprocess (e.g., chemical vapor deposition (CVD), atomic layer deposition(ALD), physical vapor deposition (PVD), etc.), an etch process (e.g.,reactive ion etch (RIE), plasma etching, etc.), or the like. Theprocessing chambers 110, 112, 114, 116, 118 may be round, rectangular,or another shape, as required by the shape of the substrate to beprocessed and other processing requirements.

The transfer chamber 106 has slit valve openings 121, 123, 125, 127,129, 131 in sidewalls between the transfer chamber 106 and the FOUP loadlock 104, first processing chamber 110, second processing chamber 112,third processing chamber 114, fourth processing chamber 116, and fifthprocessing chamber 118, respectively. The transfer robot 108 ispositioned and configured to be capable of inserting one or more tools(e.g., substrate handling blades) through each of the slit valveopenings 121, 123, 125, 127, 129, 131 and into the adjacent chamber.That is, the transfer robot 108 can insert tools into the FOUP load lock104, the first processing chamber 110, the second processing chamber112, the third processing chamber 114, the fourth processing chamber116, and the fifth processing chamber 118 via slit valve openings 121,123, 125, 127, 129, 131 in the walls of the transfer chamber 106 betweeneach of the other chambers. The slit valve openings 121, 123, 125, 127,129, 131 are selectively opened and closed with slit valves 120, 122,124, 126, 128, 130 to allow access to the interiors of the adjacentchambers when a substrate is to be inserted or removed from one of theadjacent chambers by the transfer robot 108. A substrate 102 isillustrated on the transfer robot 108 within the transfer chamber 106for transfer.

As described in further detail below, the FOUP load lock 104 includes aFOUP transfer and queueing elevator system. The FOUP transfer andqueueing elevator system, as illustrated in FIG. 1, includes verticaltrack portions 140 a and horizontal track portions 140 b (collectively,“tracks 140”) and further includes one or more shelves 142 capable ofmoving along the tracks 140. The tracks 140 support the one or moreshelves 142 and cause the one or more shelves 142 to move as describedbelow. The one or more shelves 142 can each receive a FOUP from an OHTsystem, position a FOUP for transfer into the FOUP load lock 104,receive a FOUP from the FOUP load lock 104, position a FOUP in a queuefor subsequent transfer into the FOUP load lock 104, and/or position aFOUP to provide the FOUP to the OHT system.

The transfer chamber 106, FOUP load lock 104, and processing chambers110, 112, 114, 116, 118 include one or more apertures (not shown) thatare in fluid communication with a vacuum system (e.g., a vacuum pump).The apertures provide an egress for the gases within the variouschambers. In some examples, the chambers are each connected to aseparate and independent vacuum system. In still other examples, some ofthe chambers share a vacuum system, while the other chambers haveseparate and independent vacuum systems. As illustrated, a vacuum systemis in fluid communication with the FOUP load lock 104. The vacuum systemincludes a vacuum pump 150 and a throttle valve 152 to regulate a flowof gases to or from the FOUP load lock 104. In some examples, theprocessing system 100 can be maintained in a vacuum or in a low-pressurestate by the one or more vacuum systems while one or more substrates arein and transferred between different chambers, including to and from theFOUP load lock 104, the transfer chamber 106, and the processingchambers 110, 112, 114, 116, 118.

The processing system 100 includes one or more process controllers 160,each of which may be or include a computer or system of computers. Eachprocess controller can include a processor that executes program codeinstructions stored on a tangible, non-transitory medium, such as randomaccess memory (RAM), read-only memory (ROM), etc., to perform and/orcontrol various operations described herein. The process controller (ora respective process controller) can control operations of the FOUP loadlock 104, such as movement of the one or more shelves 142 via the tracks140, transferring a FOUP into and out of the FOUP load lock 104, etc.The process controller can be in communication with a process controllerof the OHT system to coordinate delivery of a FOUP between the FOUPtransfer and queueing elevator system and the OHT system. The processcontroller (or another respective process controller) can controloperations of the transfer chamber 106, such as operations of thetransfer robot 108, opening and closing of slit valves 120, 122, 124,126, 128, 130, etc. The process controller (or other respective processcontrollers) can control operations of the processing chambers 110, 112,114, 116, 118 to implement various processing conditions according to arespective recipe. If multiple process controllers are implemented, theprocess controllers may each be in communication with one or more of theother process controllers to coordinate various operations.

As illustrated, the processing system 100 includes five processingchambers and one FOUP load lock. In other examples, a processing systemcan include any number of processing chambers and FOUP load locks. Forexample, a processing system can include four processing chambers andtwo FOUP load locks. Other numbers of processing chambers and FOUP loadlocks can be implemented.

FIG. 2 illustrates a cut-away perspective view of the processing system100 of FIG. 1, according to some examples. Many components of theprocessing system 100 that were described with respect to FIG. 1 are notillustrated in FIG. 2 to avoid obscuring various features that are to bedescribed with respect to FIG. 2. A person having ordinary skill in theart will readily understand the presence of the components in FIG. 2that are not illustrated therein.

More particularly, FIG. 2 illustrates additional details relating to theFOUP load lock 104. The FOUP load lock 104 includes an interior space202 defined by various walls (e.g., sidewalls, ceiling, and floor). TheFOUP load lock 104 is configured to receive a FOUP 204 into the interiorspace 202 for transferring substrates from, e.g., other tools in a fabto the various chambers of the processing system 100. The fabenvironment is the ambient environment outside of the processing system100, e.g., outside an exterior of the FOUP load lock 104.

Exterior to the interior space 202, the FOUP load lock 104 includes aFOUP transfer and queueing elevator system. The FOUP transfer andqueueing elevator system includes the tracks 140 (one track 140 isillustrated in FIG. 2 due to the cut-away), a first shelf 212, and asecond shelf 214. The tracks can be any belt or linkage that is motordriven, which motor can be controlled by the controller 160. The firstshelf 212 and the second shelf 214 can be mechanically attached orcoupled to the belt or linkage, if so implemented. The first shelf 212and the second shelf 214 are capable of being conveyed along the tracks140 along a lateral sidewall of the FOUP load lock 104, e.g., along thevertical track portions 140 a in a vertical direction 216, and at leastthe first shelf 212 (and, possibly, the second shelf 214) is capable ofbeing conveyed along a top of the FOUP load lock 104, e.g., along thehorizontal track portions 140 b in a horizontal direction 218. As willbe described in further detail below, when in proper positions, thefirst shelf 212 and the second shelf 214 each are capable of receiving aFOUP from an automated overhead hoist transfer (OHT) system 220. With aFOUP on one or both of the first shelf 212 and the second shelf 214, thefirst shelf 212 and the second shelf 214 can be conveyed along thetracks 140 to position the FOUP to transfer the FOUP into the interiorspace 202 of the FOUP load lock 104 and/or to queue the FOUP to awaitsubsequent transfer of the FOUP into the interior space 202. The firstshelf 212 and second shelf 214 each are capable of receiving a FOUP fromthe interior space 202, and once a FOUP is received from the interiorspace 202 on one or both of the first shelf 212 and the second shelf214, one or both of the first shelf 212 and the second shelf 214 can beconveyed along the tracks 140 to position the FOUP to transfer the FOUPto the OHT system 220.

When a FOUP is on one of the first shelf 212 or the second shelf 214,and that shelf is properly positioned along the lateral sidewall of theFOUP load lock 104, the FOUP is transferred into the interior space 202through a load lock door opening 230. A load lock isolation door 232 isoperable to be removed from the load lock door opening 230 for transferof a FOUP into the interior space 202 and to close the load lock dooropening 230 at other times. In the illustrated example, the load lockisolation door 232 is removed from the load lock door opening 230 by theload lock isolation door 232 sliding downwardly into a door pocket 233in the lateral sidewall of the FOUP load lock 104. The load lockisolation door 232 can close the load lock door opening 230 by slidingupwardly to the load lock door opening 230. The load lock isolation door232 can form a seal on the load lock door opening 230 when the load lockisolation door 232 is closed to prevent a gas from entering and/orexiting the interior space 202. The load lock isolation door 232 may bemoved by an actuator or other movement mechanism, which may further becontrolled by the controller 160.

A shuttle is operable to transfer a FOUP (e.g., FOUP 204) from the firstshelf 212 or the second shelf 214 into the interior space 202. Theshuttle includes a clamp 234, a lateral extender 236, and a verticallift 238. The clamp 234 is operable to attach to and secure a FOUP(e.g., FOUP 204) and to release the FOUP. The vertical lift 238 isoperable to move the clamp 234 vertically for proper vertical position,e.g., of the clamp 234 to attach to and/or release a FOUP and/or, whenthe clamp 234 is attached to a FOUP 204, of the FOUP. The lateralextender 236 is operable to extend the clamp 234 laterally, e.g., totransfer the FOUP 204 from the first shelf 212 or second shelf 214 intothe interior space 202 through the load lock door opening 230, or viceversa. Each of the lateral extender 236 and vertical lift 238 caninclude a track and a linkage, actuator, or other movement mechanismoriented to provide movement as described herein. Further, the shuttle(e.g., the clamp 234, the lateral extender 236, and the vertical lift238) can be controlled by the controller 160.

The interior space 202 of the FOUP load lock 104 is fluidly connected tothe vacuum system (e.g., vacuum pump 150 via throttle valve 152 (notillustrated in FIG. 2)). After transferring the FOUP 204 into the FOUPload lock 104 and closing the load lock isolation door 232 over the loadlock door opening 230, the vacuum system can pump down the interiorspace 202 to a low pressure and/or a vacuum. The FOUP 204 can be ventedduring the pump down to create a vacuum in the FOUP 204 that is inequilibrium with the interior space 202. In some examples, the FOUP 204can be fluidly coupled to the vacuum system to pump an inert gas (e.g.,nitrogen (N₂)) to the FOUP 204 and purge the inert gas from the FOUP204. The pressure of gas in the FOUP 204 can be greater than thepressure in the interior space 202. By purging an inert gas in the FOUP204, substrates in the FOUP 204 can remain clean.

The shuttle is operable to position the FOUP 204 such that a FOUP door250 of the FOUP 204 is abutting a FOUP door opener 252 of the FOUP loadlock 104. The FOUP door opener 252 is proximate an interface between theinterior space 202 of the FOUP load lock 104 and the transfer chamber106. For example, the FOUP door opener 252 is at a lateral sidewall ofthe FOUP load lock 104 (and within the interior space 202) opposite fromthe lateral sidewall of the FOUP load lock 104 that has the load lockdoor opening 230. The FOUP door opener 252 is operable to attach to theFOUP door 250 and to then open the FOUP door 250. In some examples, theFOUP door opener 252 is operable to remove the FOUP door 250 from theFOUP 204 and, with the FOUP door opener 252 attached to the FOUP door250, is operable to slide downward into a door pocket 254 of the lateralsidewall of the FOUP load lock 104. The FOUP door opener 252 may includea clamp that, when activated, attaches to the FOUP door 250, whichfurther triggers a release mechanism to release the FOUP door 250 fromthe FOUP 204. The FOUP door opener 252 can be moved by an actuator orother movement mechanism. The clamp and actuator or movement mechanismof the FOUP door opener 242 may be controlled by the controller 160.

An isolation and indexing mechanism 260 is on the lateral sidewall ofthe FOUP load lock 104 opposite from the lateral sidewall of the FOUPload lock 104 that has the load lock door opening 230. The isolation andindexing mechanism 260 encircles the interface between the interiorspace 202 of the FOUP load lock 104 and the transfer chamber 106 (e.g.,the slit valve opening 121 through the lateral sidewall). The isolationand indexing mechanism 260 is moveable along the lateral sidewall, e.g.,by implementing a glide or a track. In the illustrated example, thelateral sidewall has a cut-out in which the isolation and indexingmechanism 260 is moveable. The cut-out can function to limit themovement of the isolation and indexing mechanism 260 along the lateralsidewall. The shuttle is operable to position the FOUP 204, with theFOUP door 250 opened, such that a face of the FOUP 204 abuts theisolation and indexing mechanism 260. When the face of the FOUP 204abuts the isolation and indexing mechanism 260, a shield may be formedbetween the lateral sidewall of the FOUP load lock 104 and the FOUP 204by the isolation and indexing mechanism 260. The shuttle is operable tomove the FOUP 204 in any direction to abut the face of the FOUP 204 tothe isolation and indexing mechanism 260, such as by translation and/orrotation. The isolation and indexing mechanism 260 can include adeflector and bellow that form the shield between the lateral sidewalland the FOUP 204. A small gap may be between the FOUP 204 and thelateral sidewall to permit movement of the FOUP 204 relative to the slitvalve opening 121 through the lateral sidewall. The deflector and bellowcan shield possible particulates or contaminates from flowing throughthe gap into the transfer chamber 106. In some examples, the FOUP 204may remain stationary while abutting the isolation and indexingmechanism 260. As will become more apparent subsequently, if thetransfer robot 108 is capable of moving vertically sufficiently throughthe slit valve opening 121, the transfer robot 108 may be able to accesssubstrates in the FOUP 204 without the FOUP 204 moving while beingengaged with the isolation and indexing mechanism 260. Under suchcircumstances, the isolation and indexing mechanism 260 can beimmoveable and can form a seal between the face of the FOUP 204 and thelateral sidewall of the FOUP load lock 104. The seal may be formed by anO-ring or the like of the isolation and indexing mechanism 260. Variouspressure differentials may be created, e.g., between the interior spaceof the FOUP 204 and the interior space 202 of the FOUP load lock 104,when a seal is formed.

A sensor and/or camera (not illustrated) may be disposed in or adjacentto the slit valve opening 121 proximate the lateral sidewall. The sensorand/or camera can view into the FOUP 204 when the FOUP 204 abuts theisolation and indexing mechanism 260. The sensor and/or camera isoperable to view the substrates in the FOUP 204 and, in conjunction withthe controller 160, to determine respective positions of the substratesin the FOUP 204 to map the substrates. The controller 160 canresponsively control the shuttle to move the FOUP 204 to index thesubstrates for access by the transfer robot 108.

The FOUP load lock 104 further includes a tunnel isolation door 264 inthe slit valve opening 121 through the lateral sidewall of the FOUP loadlock 104. The tunnel isolation door 264 is operable to open and close,e.g., by an actuator controlled by the controller 160. When the tunnelisolation door 264 is in the closed position, the interior space 202may, e.g., be pumped down to a low pressure or a vacuum. When the tunnelisolation door 264 is open, which may further be in coordination withthe opening of the slit valve 120, the transfer robot 108 may access oneor more substrates in the FOUP 204 through the slit valve opening 121.

FIGS. 3 through 8 are partial cut-away perspective views of theprocessing system 100 illustrating a sequence of operations for loadingFOUPs to the FOUP load lock 104, according to some examples. Variousmovements of the first shelf 212 and the second shelf 214 are describedherein. The first shelf 212 and the second shelf 214 may be linkedtogether such that the movement of the first shelf 212 and the secondshelf 214 is coordinated and in parallel. In other examples, the firstshelf 212 may move independently of the second shelf 214.

In FIG. 3, the first shelf 212 moves to a loading position proximate theOHT system 220. Depending on an initial positioning of the first shelf212, the first shelf 212 may move in a vertical direction 216 and/or ahorizontal direction 218 along the tracks 140 to the loading position.At the loading position, any shelf is capable of receiving a FOUP fromthe OHT system 220 and/or of providing a FOUP to the OHT system 220. InFIG. 3, the first shelf 212 at the loading position receives a firstFOUP 302 from the OHT system 220. The second shelf 214 may be at anyposition along the tracks 140 when the first shelf 212 is at the loadingposition.

In FIG. 4, the first shelf 212 moves, with the first FOUP 302 thereon,to a load lock transfer position at the load lock door opening 230. Asillustrated, the first shelf 212 moves down the vertical track portions140 a in a vertical direction 216 from the loading position to the loadlock transfer position. Once at the load lock transfer position, thefirst FOUP 302 is transferred from the first shelf 212 to the interiorspace 202 of the FOUP load lock 104 through the load lock door opening230, as will be described in further detail below. The second shelf 214may be at any position along the tracks 140 when the first shelf 212 isat the load lock transfer position and/or is moving from the loadingposition to the load lock transfer position. In some examples, thesecond shelf 214 is at a queueing position (to be described below) whenthe first shelf 212 is at the load lock transfer position.

In FIG. 5, after the first FOUP 302 is transferred into the interiorspace 202, the first shelf 212 moves to a cleared position, and thesecond shelf 214 moves to the loading position. The first shelf 212moves, after the first FOUP 302 is transferred into the interior space202, from the load lock transfer position to the cleared position bymoving up the vertical track portions 140 a in a vertical direction 216and across the horizontal track portions 140 b in a horizontal direction218. In the illustrated example, the cleared position is above theceiling defining the interior space 202, although in other examples, thecleared position may be located at a different position. The secondshelf 214 moves up the vertical track portions 140 a in a verticaldirection 216 to the loading position proximate the OHT system 220. Withthe first shelf 212 in the cleared position, the second shelf 214 maymove to the loading position, and may receive a FOUP from the OHT system220, without obstruction from the first shelf 212. The second shelf 214at the loading position receives a second FOUP 304 from the OHT system220.

In FIG. 6, after the second shelf 214 receives the second FOUP 304, thesecond shelf 214 moves from the loading position to a queueing position,and the first shelf 212 moves from the cleared position to the load locktransfer position. The second shelf 214 moves down the vertical trackportions 140 a in a vertical direction 216 from the loading position tothe queueing position. The first shelf 212 moves across the horizontaltrack portions 140 b in a horizontal direction 218 and then down thevertical track portions 140 a in a vertical direction 216 from thecleared position to the load lock transfer position. In the load locktransfer position, the first shelf 212 awaits completion of processingof substrates that were transferred into the FOUP load lock 104 by thefirst FOUP 302. Once processing of those substrates is complete, thefirst FOUP 302 will be transferred from the interior space 202 to thefirst shelf 212. In the queueing position, the second shelf 214, withthe second FOUP 304 thereon, is clear of the first shelf 212 moving intothe load lock transfer position, and the second shelf 214, with thesecond FOUP 304 thereon, awaits the transferring the first FOUP 302 outof the interior space 202 and subsequently moving the first shelf 212,with the first FOUP 302 thereon, away from the load lock door opening230.

In FIG. 7, the first FOUP 302 is transferred, through the load lock dooropening 230, from the interior space 202 to the first shelf 212 at theload lock transfer position. Additional details of this transfer aredescribed below.

In FIG. 8, after the first FOUP 302 is transferred to the first shelf212, the first shelf 212 moves up the vertical track portions 140 a in avertical direction 216 to the loading position, and the second shelf214, with the second FOUP 304 thereon, moves up the vertical trackportions 140 a in a vertical direction 216 to the load lock transferposition. Once at the load lock transfer position, the second FOUP 304is transferred from the second shelf 214 to the interior space 202 ofthe FOUP load lock 104 through the load lock door opening 230. At theloading position, the first shelf 212 provides the first FOUP 302 to theOHT system 220, which may remove the first FOUP 302 from the first shelf212.

After the OHT system 220 unloads the first FOUP 302 from the first shelf212 and after the second FOUP 304 is transferred into the interior space202, the first shelf 212 moves to the cleared position, and the secondshelf 214 moves to the loading position, as described with respect toFIG. 5. At the loading position, the second shelf 214 receives anotherFOUP from the OHT system 220, and the cycle of FIGS. 5 through 8 can berepeated for any number of FOUPs.

FIGS. 9 through 11 are partial cut-away perspective views of theprocessing system 100 illustrating a sequence of operations fortransferring a FOUP into and/or out of the interior space 202 of theFOUP load lock 104 and for transferring substrates between the FOUP andthe transfer chamber 106, according to some examples. Each FOUPdelivered to the FOUP load lock 104 can have one or multiple substrates(e.g., up to 25 substrates, in some examples) enclosed therein. Eachsubstrate may be disposed in a slot in the FOUP for transport.

As shown in FIG. 9, and as described above with respect to FIGS. 4and/or 8, a FOUP 402 (e.g., first FOUP 302 or second FOUP 304) isprovided on a shelf 404 (e.g., first shelf 212 or second shelf 214) atthe load lock transfer position. In the illustrated state, the interiorspace 202 of the FOUP load lock 104 is closed off from other chambersand any other ambient environment in which the FOUP load lock 104 isdisposed (e.g., the environment inside the fab). For example, the loadlock isolation door 232 and tunnel isolation door 264 are in closedpositions, and any valve of the vacuum system that is in fluidconnection with the interior space 202 is closed. One or more valves(e.g., of the vacuum system) between the interior space 202 and theambient environment may be opened and/or a gas (e.g., an ambient gasand/or inert gas) may be pumped into the interior space 202 to bring thepressure of the interior space 202 into equilibrium with the ambientenvironment (which may be approximately 1 atm).

With the interior space 202 at a pressure that is at equilibrium withthe ambient environment, the load lock isolation door 232 is removedfrom the load lock door opening 230. For example, the load lockisolation door 232 is moved downwardly into the door pocket 233 of thesidewall of the FOUP load lock 104 to remove the load lock isolationdoor 232 from the load lock door opening 230.

The shuttle moves, by the vertical lift 238, to position the clamp 234vertically at a level above the FOUP 402 on the shelf 404 and below anupper boundary of the load lock door opening 230. The shuttle thenmoves, by the lateral extender 236, the clamp 234 laterally out the loadlock door opening 230 and positions the clamp 234 directly above theFOUP 402. The vertical lift 238 then lowers the clamp 234 to engage andattach to the FOUP 402. With the clamp 234 attached to the FOUP 402, thevertical lift 238 raises the clamp 234, and hence, also the FOUP 402,which lifts the FOUP 402 from the shelf 404. The lateral extender 236then retracts to bring the clamp 234 and attached FOUP 402 through theload lock door opening 230 into the interior space 202.

Referring to FIG. 10, with the FOUP 402 transferred into the interiorspace 202, the load lock isolation door 232 is moved to close the loadlock door opening 230. For example, the load lock isolation door 232 ismoved upwardly from the door pocket 233 of the sidewall of the FOUP loadlock 104 to cover the load lock door opening 230. With the load lockisolation door 232 closing the load lock door opening 230, the vacuumsystem pumps down the interior space 202 to a lower pressure or avacuum. The FOUP 402 can be vented during the pump down to create avacuum in the FOUP 402 that is in equilibrium with the interior space202.

The shuttle positions the FOUP 402 such that the FOUP door 406 of theFOUP 402 engages the FOUP door opener 252. The shuttle can use thelateral extender 236 (for lateral movement) and/or the vertical lift 238(for vertical movement) to position the FOUP 402 such that the FOUP door406 engages the FOUP door opener 252. By engaging the FOUP door opener252, the FOUP door 406 is released from a face of the FOUP 402. The FOUPdoor opener 252, with the FOUP door 406 engaged, removes the FOUP door406 from the face of the FOUP 402, such as downwardly into the doorpocket 254 of the sidewall of the FOUP load lock 104.

The positioning of substrates in the FOUP 402 is mapped. The sensorand/or camera in the slit valve opening 121 can detect the position ofthe substrates in the FOUP 402, which in conjunction with the controller160, can be used to map the positioning of the substrates.

Referring to FIG. 11, the shuttle positions the FOUP 402 such that theface of the FOUP 402 engages the isolation and indexing mechanism 260.The isolation and indexing mechanism 260 can form a shield around theface of the FOUP 402 from the lateral sidewall of the FOUP load lock104. The vacuum system may further pump down the interior space 202 tomaintain and/or create a vacuum in the interior space 202. The vacuumsystem or another gas system can increase a pressure of an inert gas(e.g., nitrogen (N₂) gas) in the transfer chamber 106 to be greater thanthe pressure of gas in the interior space 202 of the FOUP load lock 104.In some examples, the isolation and indexing mechanism 260 forms a sealbetween the face of the FOUP 402 from the lateral sidewall of the FOUPload lock 104.

The tunnel isolation door 264 is opened, and the slit valve 120 isopened. The pressures in the FOUP 402 and transfer chamber 106 aretherefore equalized. With the tunnel isolation door 264 and slit valve120 open, the transfer robot 108 can extend through the slit valveopening 121 to access a substrate in the FOUP 402. With the tunnelisolation door 264 and slit valve 120 open, due to the pressuredifferential between the transfer chamber 106 and the FOUP load lock104, the inert gas can flow from the transfer chamber 106 through anygap between the lateral sidewall of the FOUP load lock 104 and the FOUP402. This flow of the inert gas can reduce particulates andcontamination that may flow into the transfer chamber 106. Additionally,an inert gas can be pumped into the FOUP 402 to create a greaterpressure in the FOUP 402 than the interior space 202, which can helpreduce particulates and contamination inside the FOUP 402.

Once the transfer robot 108 accesses a substrate, the transfer robot 108can retract back through the slit valve opening 121 with the substrate.The transfer robot 108 can then transfer the substrate to any of theprocessing chambers 110, 112, 114, 116, 118 for processing according tothe particular chamber. The transfer robot 108 can further transfer theprocessed substrate to and between different ones of the processingchambers 110, 112, 114, 116, 118. After processing of the substrate, thetransfer robot 108 can remove the substrate from one of the processingchambers 110, 112, 114, 116, 118. The slit valve 120 and tunnelisolation door 264 then open, and the transfer robot 108 extends, withthe processed substrate, through the slit valve opening 121 to transferthe substrate back to the FOUP 402.

In some examples, the shuttle can further vertically move the FOUP 402,while the face of the FOUP 402 remains engaged with the isolation andindexing mechanism 260, to index a particular substrate or positionwithin the FOUP 402 with the transfer robot 108. As indicated above, theFOUP 402 can have multiple slots, where each slot may have a substrate.When engaged with the isolation and indexing mechanism 260, eachsubstrate in the FOUP 402 is generally oriented horizontally such thatthe substrate can be transferred through the slit valve opening 121without rotation. The shuttle can therefore vertically lift the FOUP 402to align a substrate or position in the FOUP 402 such that the transferrobot 108 can access the substrate or position in the FOUP 402. Theisolation and indexing mechanism 260 can remain engaged with the face ofthe FOUP 402 while the shuttle vertically aligns the FOUP 402 such thatthe transfer robot 108 can access a particular substrate or position inthe FOUP 402. In some examples, the transfer robot 108 is capable ofmoving vertically sufficiently through the slit valve opening 121, andthe shuttle does not vertically move the FOUP 402. In such examples, theisolation and indexing mechanism 260 can form a seal between the face ofthe FOUP 204 and the lateral sidewall of the FOUP load lock 104.

Any number of substrates can be removed from and/or remain in the FOUP402 at any given time while the FOUP 402 is in the FOUP load lock 104.For example, each of the processing chambers 110, 112, 114, 116, 118 mayhave a substrate for processing at any time. Hence, the transfer robot108 can remove an appropriate number of substrates from the FOUP 402before transferring any of those substrates back to the FOUP 402.

Once the processed substrates are transferred back to the FOUP 402, theslit valve 120 and tunnel isolation door 264 are closed. The interiorspace 202 and the FOUP 402 are brought into equilibrium with the FOUP402 de-coupled from the pressure of the transfer chamber. The shuttlelaterally moves the FOUP 402 to disengage from the isolation andindexing mechanism 260. The FOUP door opener 252 moves (e.g., verticallyupward from the door pocket 254 in the illustrated example) to place theFOUP door 406 on the face of the FOUP 402. The vacuum system can thenopen a valve to the ambient environment to bring the pressure of theinterior space 202 into equilibrium with the ambient environment. Withthe interior space 202 at a pressure that is in equilibrium with thepressure of the ambient environment, the load lock isolation door 232 isremoved from the load lock door opening 230 (e.g., by moving the loadlock isolation door 232 downwardly into the door pocket 233). Theshuttle then moves the FOUP 402 through the load lock door opening 230and onto a shelf (which may be the shelf 404 or a different shelf), suchas described with respect to and illustrated by FIG. 7. After placingthe FOUP 402 on the shelf, the shuttle retracts back to the interiorspace 202 and the load lock isolation door 232 closes the load lock dooropening 230.

FIG. 12 is a simplified schematic top view of another illustrativeprocessing system 500, according to some examples. The processing system500 includes components that are included in the processing system 100of FIG. 1, and hence, description of those components is omitted forbrevity. The processing system 500 includes a batch processing chamber502 with a slit valve 504 and slit valve opening 505 between the batchprocessing chamber 502 and the transfer chamber 106. The transfer robot108 can transfer substrates between the transfer chamber 106 and thebatch processing chamber 502 via the slit valve opening 505 similar toas described above. The batch processing chamber 502 can processmultiple substrates simultaneously. A person having ordinary skill inthe art will readily understand other modification to implement theprocessing system 500. Further, the processing system 500 can include onor more additional processing chambers, which may be single substrate orbatch processing chambers, and can include one or more additional FOUPload locks.

As described herein, some examples implement a FOUP load lock in aprocessing system. The FOUP load lock can obviate the need for costlyand large equipment. Hence, the FOUP load lock can reduce costs and afootprint of the processing system. This can enable standaloneapplications for improved research and development placement.Additionally, an elevator system implemented with the FOUP load lock canreduce downtime of a processing system that might otherwise beassociated with waiting on delivery of a FOUP. This can increasethroughput of substrates through a processing system. Even further,fewer substrate (e.g., wafer) handling operations can be implemented byprocesses that use the FOUP load lock, which can in turn reduce possibleexposure to dust or other particles that could be problematic.

While the foregoing is directed to embodiments of the presentdisclosure, other and further embodiments of the disclosure may bedevised without departing from the basic scope thereof, and the scopethereof is determined by the claims that follow.

1. A processing system for processing a substrate, the processing systemcomprising: a Front Opening Unified Pod (FOUP) load lock having wallsdefining an interior space therein, the FOUP load lock comprising: aload lock isolation door operable to close a load lock isolation dooropening in a first sidewall of the FOUP load lock, the load lockisolation door opening being sized so that a FOUP is capable of passingtherethrough to and from the interior space; and a tunnel isolation dooroperable to close a first slit valve opening in a second sidewall of theFOUP load lock, the first slit valve opening being sized so that asubstrate capable of being placed in the FOUP is capable of passingthrough the first slit valve opening to and from the interior space; anda vacuum system fluidly connected to the interior space of the FOUP loadlock, the vacuum system being operable to pump down a pressure of theinterior space of the FOUP load lock.
 2. The processing system of claim1 further comprising: a transfer chamber attached to the FOUP load lock,the transfer chamber comprising a transfer robot, the transfer robotbeing operable to transfer a substrate from the FOUP in the FOUP loadlock to the transfer chamber via the first slit valve opening; and aprocessing chamber attached to the transfer chamber, the transfer robotbeing operable to transfer a substrate from the transfer chamber to theprocessing chamber via a second slit valve opening.
 3. The processingsystem of claim 1, wherein the FOUP load lock further comprises: a FOUPelevator system comprising a first shelf and a second shelf, the firstshelf and the second shelf being operable to move at least along thefirst sidewall of the FOUP load lock, the first shelf and the secondshelf being operable to move to a loading position to receive or providea FOUP and to move to a load lock transfer position to transfer a FOUPthrough the load lock isolation door opening to or from the interiorspace, the first shelf being operable to move to a cleared position whenthe second shelf is in the loading position, the second shelf beingoperable to move to a queueing position when the first shelf is in theload lock transfer position.
 4. The processing system of claim 1,wherein the FOUP load lock further comprises: a shuttle comprising aclamp, a lateral extender, and a vertical lift, the shuttle beingoperable to attach to the FOUP using the clamp and to move the FOUPthrough the load lock isolation door opening and within the interiorspace by lateral movement using the lateral extender and by verticalmovement using the vertical lift, the shuttle further being operable toposition the FOUP at the second sidewall of the FOUP load lock foraccess to a substrate in the FOUP through the first slit valve opening.5. The processing system of claim 1, wherein the FOUP load lock furthercomprises: a FOUP door opener operable to engage a FOUP door and removethe FOUP door from the FOUP.
 6. The processing system of claim 1,wherein the FOUP load lock further comprises: an isolation and indexingmechanism on the second sidewall of the FOUP load lock and surroundingthe first slit valve opening, the isolation and indexing mechanism beingoperable to engage a face of the FOUP and being operable to move alongthe second sidewall when the FOUP is moved to index the FOUP.
 7. Amethod for providing a substrate to a processing system, the methodcomprising: positioning a first Front Opening Unified Pod (FOUP) at aload lock door opening of a FOUP load lock; using a shuttle,transferring the first FOUP through the load lock door opening to aninterior space of the FOUP load lock; after transferring the first FOUPto the interior space, pumping down a pressure of the interior space;and using the shuttle, positioning the first FOUP at a slit valveopening of the FOUP load lock.
 8. The method of claim 7 furthercomprising accessing, via the slit valve opening, a substrate in thefirst FOUP by a transfer robot of a transfer chamber, the transferchamber being attached to the FOUP load lock.
 9. The method of claim 7further comprising mapping respective positions of substrates in thefirst FOUP while the first FOUP is in the interior space.
 10. The methodof claim 7, wherein positioning the first FOUP at the load lock dooropening comprises: receiving the first FOUP on a shelf of a FOUPelevator system of the FOUP load lock from an overhead hoist transfer(OHT) system; and moving the shelf to the load lock door opening withthe first FOUP on the shelf.
 11. The method of claim 7 furthercomprising: while the first FOUP is in the interior space: receiving asecond FOUP on a shelf of a FOUP elevator system of the FOUP load lockfrom an overhead hoist transfer (OHT) system; and moving the shelf to aqueueing position with the second FOUP on the shelf.
 12. The method ofclaim 7 further comprising: using the shuttle, transferring the firstFOUP from the interior space through the load lock door opening to afirst shelf of a FOUP elevator system of the FOUP load lock; moving thefirst shelf, with the first FOUP on the first shelf, to a loadingposition to provide the first FOUP to an overhead hoist transfer (OHT)system; moving a second shelf of the FOUP elevator system, with a secondFOUP on the second shelf, from a queueing position to the load lock dooropening; using the shuttle, transferring the second FOUP from the secondshelf through the load lock door opening to the interior space; aftertransferring the second FOUP from the second shelf, moving the secondshelf to the loading position; receiving a third FOUP on the secondshelf at the loading position from the OHT system; moving the secondshelf, with the third FOUP on the second shelf, to the queueingposition; and moving the first shelf, without a FOUP on the first shelf,to the load lock door opening, the first shelf without a FOUP thereonbeing at the load lock door opening while the second shelf with thethird FOUP thereon is at the queueing position.
 13. The method of claim12, wherein the first shelf moves at least vertically between the loadlock door opening and the loading position, and the second shelf movesat least vertically between the queueing position and the load lock dooropening and between the load lock door opening and the loading position.14. The method of claim 12 further comprising moving the first shelf toa cleared position, the first shelf being in the cleared position whenthe second shelf is in the loading position.
 15. The method of claim 14,wherein: the first shelf moves at least vertically between the load lockdoor opening and the loading position; the first shelf moves at leastlaterally between the loading position and the cleared position; and thesecond shelf moves at least vertically between the queueing position andthe load lock door opening and between the load lock door opening andthe loading position.
 16. A processing system for processing asubstrate, the processing system comprising: a Front Opening Unified Pod(FOUP) load lock being configured to receive a FOUP in an interior spaceof the FOUP load lock; a vacuum system fluidly connected to the interiorspace of the FOUP load lock, the vacuum system being operable to pumpdown a pressure of the interior space of the FOUP load lock; a transferchamber attached to the FOUP load lock, the transfer chamber comprisinga transfer robot, the transfer robot being operable to transfer asubstrate from the FOUP in the interior space to the transfer chamber;and a processing chamber attached to the transfer chamber, the transferrobot being operable to transfer a substrate from the transfer chamberto the processing chamber.
 17. The processing system of claim 16,wherein the FOUP load lock comprises: a load lock isolation dooroperable to close a load lock isolation door opening in a first sidewallof the FOUP load lock, the load lock isolation door opening being sizedso that the FOUP is capable of passing therethrough to and from theinterior space; and a tunnel isolation door operable to close a slitvalve opening in a second sidewall of the FOUP load lock, the slit valveopening being sized so that a substrate capable of being placed in theFOUP is capable of passing through the slit valve opening to and fromthe interior space, the transfer robot being operable to transfer asubstrate from the transfer chamber to the processing chamber via theslit valve opening.
 18. The processing system of claim 16, wherein theFOUP load lock further comprises: a FOUP elevator system comprising afirst shelf and a second shelf moveable along a track, wherein: thefirst shelf and the second shelf are moveable along the track to aloading position to receive or provide a FOUR; the first shelf and thesecond shelf are moveable along the track to a load lock transferposition to transfer a FOUP to or from the interior space; the firstshelf is movable along the track to a cleared position when the secondshelf is at the loading position; and the second shelf is moveable alongthe track to a queueing position when the first shelf is at the loadlock transfer position.
 19. The processing system of claim 16, whereinthe FOUP load lock further comprises: a shuttle comprising a clamp, alateral extender, and a vertical lift, the shuttle being operable toattach to the FOUP using the clamp and to move the FOUP through a loadlock door opening of the FOUP load lock and within the interior spaceusing the lateral extender and the vertical lift, the shuttle furtherbeing operable to position the FOUP at a sidewall of the FOUP load lockfor access to a substrate in the FOUP by the transfer robot.
 20. Theprocessing system of claim 16, wherein the FOUP load lock furthercomprises: a FOUP door opener operable to engage a FOUP door and removethe FOUP door from the FOUP.